CN1253601A

CN1253601A - Stable web having enhanced extensibility and method for making same

Info

Publication number: CN1253601A
Application number: CN98804610A
Authority: CN
Inventors: 道格拉斯·H·本森; 约翰·J·柯罗
Original assignee: Procter and Gamble Co
Current assignee: Procter and Gamble Co
Priority date: 1997-04-04
Filing date: 1998-04-02
Publication date: 2000-05-17
Also published as: TR199902398T2; ES2177002T3; AR012332A1; NO994805L; AU7101298A; DE69806235D1; DE69806235T2; EG21581A; WO1998045520A1; PE70699A1; CA2284702C; TW391870B; HUP0001990A3; BR9808469A; IL132015A0; CO5031278A1; HUP0001990A2; ZA982875B; ID27866A; EP0972101A1

Abstract

The present invention provides a stable nonwoven web having enhanced extensibility and a method for making the same. A neckable nonwoven web is fed in a first direction. The neckable nonwoven web is subjected to incremental stretching in a direction perpendicular to the first direction. A tensioning force is applied to the neckable nonwoven web to neck the nonwoven web. The necked nonwoven web is then subjected to mechanical stabilization to provide a stabilized extensible necked nonwoven web. The stabilized extensible necked nonwoven web is easily extended in a direction parallel to the direction necking.

Description

Have the stable wire side and the manufacture method thereof that strengthen ductility

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a kind of machinery back processing method that has the stabilizing material that strengthens ductility and make this material.High ductility material, for example nonwoven web and film wire side, especially be suitable for the disposable absorbent article such as diaper, incontinent brief, training pants, feminine hygiene clothing, reason is that this material can be used in needs high ductibility to assist the position of body fitting on the articles for use.

The background technology of invention

Nonwoven web can be made the parts on articles for use and the articles for use at low cost, and is promptly discardable after once or several times using.Typical products comprises similar articles for use such as diaper, training pants, rag, clothing, incontinent brief, feminine hygiene clothing.

Also can handle nonwoven web makes it have some characteristic.For example, on September 14th, 1993 was authorized Hassenboehler, and people's such as Jr. U.S. Patent No. 5,244,482 has disclosed a kind of method of handling nonwoven web.In this method nonwoven web is heated also simple tension so that solidify and stable nonwoven web under a temperature that increases.The feature of this nonwoven web after processing is rendered as the elasticity of enhancing.This elasticity increase is regarded as owing to heating nonwoven web new " memory " of injecting is formed.Strengthen the stiff articles for use of ductility for hope and then do not need similar heating.In addition, this simple tension and under elevated temperature the nonwoven web made of heating usually cause tendering of fiber and nonwoven web to show stronger gloss.For many and articles for use contact skin, diaper sheath for example, above-mentioned characteristic is just moulded sense (low luster) etc. with desired softness, nothing, and to be similar to the feature of cloth opposite.At last, for making nonwoven web curing and stable heating process increase complexity and the cost handled.

The U.S. Patent No. 4,981,747 of authorizing Morman on January 1st, 1991 has disclosed a kind of " reversible " shrink-down material.Unsettled shrink-down material must be wrapped on the rewinding roller under the state of high degree of drawing, till the execution heat treatment step makes material settling out.The above-mentioned many disadvantages of listing at preferred contact skin sex aids will appear in this material, and what strengthen is the elasticity of material but not ductility.

The U.S. Patent No. 5,226,992 of authorizing Morman on June 13rd, 1993 has disclosed a kind of method that composite elastic shrinks binding material of producing.Tensile force acts at least a shrinkable material.For example the neckable nonwoven web face shrinks material or curing.Replace the nonwoven web that heating has been solidified, the method that this patent is announced is, when the curing nonwoven web that stretches is in extended state, the curing nonwoven web that stretches is superimposed upon on the elastomeric material and with itself and elastomeric material combines.By when the curing nonwoven web that stretches is in extended state it being combined with elastomeric material, nonwoven web is restricted to the size of its contraction.For the stable extending wire side of production, and nonwoven web is not attached to the added resilience layer, this patent does not provide method.

The purpose of this invention is to provide a kind of stable extensible necked nonwoven web.The form that it can be wound in the roll shaft shape or knot is knitted (festooned) is convenient to postorder conversion or applied in any combination.

Another object of the present invention provides a kind of stable extensible necked nonwoven web that can pass through the quick extension of mechanical stretching mode.

Further object of the present invention is to provide a kind of back processing method for producing stable extensible necked nonwoven web.

Another object of the present invention is to make a living produce to produce stable extensible necked nonwoven web a kind of back processing method is provided, this method does not require the heating shrinkable material to a certain elevated temperature, improves neckable nonwoven web face ductility and non-resilient and keep its primary characteristic substantially.

As used herein term " elasticity " refer to (promptly the elongating) at least 60% that anyly under the tension force effect, can stretch (promptly in addition the length of tensile force be at least after it loosens not 1.6 times of afterburning length), and recover 55% material at least discharging tensile force after-drawing amount.

Term " ductility " refers to and anyly can stretch 60% and unlikely (the back length that promptly stretches be at least after it loosens not 1.6 times of afterburning length) of serious failure at least under the tension force effect as used herein, but recovers material less than 55% discharging tensile force after-drawing amount.

Term " highly-malleable " refers to and anyly can stretch 100% and unlikely (the back length that promptly stretches be at least after it loosens not 2 times of afterburning length) of serious failure at least under the tension force effect as used herein, but recovers material less than 55% discharging tensile force after-drawing amount.

Term " is stablized " to refer to and can be stored mode with any conventional or habitual wire side and deposit and do not need to heat or additional bond makes material among the present invention of material settling out as used herein.This class location mode comprises such as low stretching spool or knot and is woven in material in the box.

Term " nonwoven web " refers to and has the individual fibers that interweaves with irregular mode or the wire side of silk thread structure as used herein.In the past, can make nonwoven web by kinds of processes.For example melt-blown process, spunbond technology and bonding carded technology.

Term " shrink-down material " refers to by applying any material that the tensile force vertical with wishing shrinkage direction makes it shrink at least one direction as used herein.

Term " shrinkable material " refers to any material that is retracted as used herein.

As used herein term " shrinking percentage " refer to shrinkable material do not shrink size and stable contraction size in the difference of shrinkage direction divided by not shrinking size and multiply by the ratio of 100 back gained.

Term " composite elastic material " refers to and has comprised the material that is attached to the elastic component in the stable extending shrink-down material as used herein.Mode that elastic component not only can discontinuous point but also the mode that can bond continuously are attached to be stablized in the extending shrink-down material.In conjunction with being at elastic component and stable extending shrink-down material is in and finish during interposed structure.The shrinkage direction of the extending shrink-down material that the elasticity direction of composite elastic material is common and stable is parallel, and can be stretched to the breakaway poing of stable extending shrink-down material along this direction.Composite elastic material can comprise more than two-layer material.

Term " polymer " as used herein " usually including but not limited to homopolymers, copolymer such as block polymer, graft polymers, irregular polymer, alternate copolymer, terpolymer etc.And composition thereof and modified material.And, unless outside special the qualification, term " polymer " " comprise all possible molecular geometry of material.These structures comprise balanced symmetry, with symmetry and irregular symmetry, but also be not limited thereto.

Term " surface-pathlength " refers to the length of measuring along the external form surface of this material assigned direction as used herein.

Summary of the invention

The invention provides a kind of method of making stable extensible necked nonwoven web, comprise the following steps:

The neckable nonwoven web face is provided;

Send the neckable nonwoven web face to along first direction;

Make the neckable nonwoven web face on the direction vertical, bear incremental stretching with first direction;

Along the direction parallel the neckable nonwoven web face is applied tensile force, it is shunk on the direction vertical with first direction with first direction;

Make the nonwoven web of contraction bear mechanical stabilization, so that obtain stable extensible necked nonwoven web.

Stable extensible necked nonwoven web can stretch easily with perpendicular direction of first direction or the direction parallel with shrinkage direction.The method for optimizing of mechanically stable contraction nonwoven web comprises makes the contraction nonwoven web bear the stretching of growth on the direction parallel with first direction.

This method also can comprise and stable extensible necked nonwoven web being wrapped on the material receiving roller or knot is woven in this additional step in the box.

This method also can comprise stable extensible necked nonwoven web is attached in the elastomeric material to form this additional step of composite elastic material.

If material is a Stretch material, then can make it to shrink by stretching along the direction vertical with the expectation shrinkage direction.Shrinkable material can be any material that at room temperature can effectively shrink.This class shrinkable material comprises the knitting and loose fabric that is spun into, bonding carded nonwoven web, spunbond nonwoven web or melt-blown nonwoven wire side.Shrinkable material can have multilayer, for example many spunbond layers and/or many meltblown layers, perhaps thin layer.Shrinkable material can be made by polymer, for example TPO.Typical TPO material comprises polypropylene, polyethylene, ethylene copolymer, propylene copolymer and composition thereof.The neckable nonwoven web face can be non-elastomeric nonwoven wire side, for example non-resilient non-woven material.

Brief Description Of Drawings

Be used to specifically note and clearly show to be claims of claimed invention although present invention includes; can believe; can better understanding be arranged to the present invention by explanation below in conjunction with the preferred embodiment of the present invention that accompanying drawing carried out; wherein; same label is used for not being essentially identical part, wherein:

Fig. 1 is a schematic diagram of making contraction nonwoven web illustrative processes process of the present invention;

Fig. 2 is the enlarged perspective of horizontal wire side intensifier;

Fig. 3 is an enlarged perspective of stablizing roller bench;

Fig. 4 is the plane of exemplary neckable nonwoven web face before stretching and contraction;

Fig. 5 is the plane of exemplary contraction nonwoven web;

Fig. 6 is the plane of exemplary composite elastic material under a part exhibition state;

Fig. 7 is a schematic diagram of making another illustrative processes process of contraction nonwoven web of the present invention;

Fig. 8 is unsuitable for being shaped shrinking the plane of the interband of nonwoven web apart from the burr pattern;

Fig. 9 is suitable for being shaped the plane of the burr pattern of the present invention that shrinks nonwoven web;

Figure 10 is suitable for being shaped the plane of another burr pattern among the present invention who shrinks nonwoven web.

Detailed description of the invention

With reference to Fig. 1, show the technology 10 of making the stable extending contraction wire side among the present invention.

According to the present invention, when feed roller 13 during around direction rotation shown in the other arrow of roller, the neckable nonwoven web face launches and along direction shown in the wire side upper arrow, also is that machine direction, MD direction or first direction are sent to from feed roller 13.The neckable nonwoven web face of sending from feed roller 13 passes nip 14, and nip is that two the

incremental stretching rollers

15 and 16 by wire side intensifier 17 between horizontal stroke constitute.

Neckable nonwoven web face 12 can be made by known nonwoven extrusion process, for example melt-blown process or spunbond technology.Directly pass nip 14 then, needn't at first leave on the feed roller.

Fig. 2 is the enlarged perspective of the preferred embodiment of horizontal wire side intensifier 17.This device is to be made of the applicator with three-dimensional surface and intermeshing at least to a certain extent two relative directions.Horizontal wire side intensifier 17 shown in Fig. 2 is made up of incremental stretching roller 15 and 16.Neckable nonwoven web face 12 passes the nip 14 that

incremental stretching roller

15 and 16 constitutes when direction shown in the arrow is rotated.Last incremental stretching roller 15 has been covered with a large amount of tooth 18 and corresponding grooves 19 along whole roller circumferential surface.Following incremental stretching roller 16 has been covered with a large amount of tooth 20 and corresponding grooves 21 along whole roller circumferential surface.Tooth 18 on the roller 15 is meshed with groove 21 on the roller 16, and the tooth 20 on the roller 16 is meshed with groove 19 on the roller 15 simultaneously.

Tooth 18 on the

roller

15 and 16 with 20 along with the parallel direction of neckable nonwoven web face 12 feeding directions, promptly vertical with neckable nonwoven web face 12 widths direction is extended.That is

tooth

18 and 20 extends along being parallel to machine direction, MD direction or first direction.

Incremental stretching roller

15 and 16 is along open up a nonwoven web with the perpendicular direction of first direction or machine direction cumulatively, make nonwoven web fiber at least to a certain extent along laterally, the CD direction or with the perpendicular direction of first direction location.Except along each bar fiber of CD direction location nonwoven web, also will increase along the CD direction or with nonwoven web surface-pathlength that the perpendicular direction of first direction is surveyed.After nonwoven web 12 withdraws from horizontal wire side intensifier 17, just produce many wrinkle 22 on the nonwoven web 12.With enter horizontal wire side intensifier 17 before open and flat substantially nonwoven web 12 compare, wrinkle 22 make the surface-pathlength of nonwoven web increase.

As can be seen from Figure 2, before the nip 14 that enters horizontal wire side intensifier 17 formations, nonwoven web is Z in the surface-pathlength of CD direction.Nonwoven web produces many wrinkle 22 after the effect of having born

incremental stretching roller

15 and 16, make nonwoven web 12 had more previous CD to the longer new CD of surface-pathlength Z to surface-pathlength Z '.CD is preferably long by 10% than Z at least to surface-pathlength Z ', more preferably grows to fewly 20%, can grow to few 30% just preferred.CD can reach 200% of size Z to surface-pathlength Z ' to nonwoven web under the situation of serious failure not occurring, even more.For example, the CD of nonwoven web 12 is 10 inches to surface-pathlength Z, and the CD that exhibition is opened after 50% is 15 inches to surface-pathlength Z '.

The method of measuring the nonwoven web surface-pathlength can find by method of testing one joint of part after this detailed description.

Incremental stretching roller

15 and 16 can comprise the tooth and the groove of any amount as required.In addition, tooth and groove can also be non-linear, for example curve, sine, zigzag etc.The size of tooth and engagement and quantity can depend on the circumstances on the

incremental stretching roller

15 and 16.

Neckable nonwoven web face 12 after coming out from horizontal wire side intensifier 17 passes the nip 25 of S forming roll cartridge 26, and this nip is made of folded formula roller 28 and 30.Neckable nonwoven web face 12 passes the nip 25 of S forming roll device 26 along the anti-S path shown in the rotation direction arrow on the folded formula roller 28 and 30.After passing S forming roll device 26, neckable nonwoven web face 12 enters the

incremental stretching roller

34 and 36 nips 32 that constitute of mechanically stable device 38.Because the roller peripheral velocity of S forming roll device 26 is controlled to be the roller peripheral velocity that is lower than mechanically stable device 38, neckable nonwoven web face 12 is just stretched between the incremental stretching roller 34 of S forming roll device 26 and mechanically

stable device

38 and 36 formed nips 32.By adjusting the speed difference between roller, the neckable nonwoven web face is stretched and is shunk desired ratio, keeps the state of this stretching after-contraction simultaneously.Mechanically stable device 38 provides the stable contraction nonwoven web that can combine with other materials.

When nonwoven web 12 was subjected to stretching between S forming roll device 26 and

incremental stretching roller

34 and 36 nips 32 that form, tensile force just imposed on the neckable nonwoven web face along being parallel to first direction, machine direction or MD direction.Along paralleling direction stretched non-woven wire side 12, make it on perpendicular to the direction of first direction or be parallel to CD and on horizontal direction, shrink with first direction.

When entering S forming roll device 26, nonwoven web 12 has CD to surface-pathlength Z '.When between the nip 26 of the incremental stretching roller 34 of S forming roll device 26 and mechanically

stable device

38 and 36, being subjected to stretching, nonwoven web 12 shrinks and has than CD to the little CD surface-pathlength Z of surface-pathlength Z ' ", preferably also little to surface-pathlength Z than CD.CD is to surface-pathlength Z " preferably less than 75% of size Z, is more preferably less than 50% of size Z.Most preferably size Z is " less than 30% of size Z.For example, the CD of nonwoven web 12 is 10 inches to surface-pathlength Z, and the CD surface-pathlength Z ' through Zhan Zhanghou expands to 15 inches of length is punctured into CD surface-pathlength Z then again, and " 5 inches, at this moment Z " is exactly 50% of former CD surface-pathlength Z.

Can also use additive method stretching neckable nonwoven web face 12, for example adopt tenter frame apparatus.

Neckable nonwoven web face 12 can be ductile, resilient or inelastic non-woven material.Neckable nonwoven web face 12 can be spunbonded webs, melt and spray wire side or the carded wire side that bonds.The wire side that if the neckable nonwoven web face is a meltblown fibers to be made.Then it can comprise melt-blown micro-fiber.The neckable nonwoven web face can be made by the fiber that forms polymer, for example the TPO material.Typical TPO material comprises one or more in polypropylene, polyethylene, ethylene copolymer, propylene copolymer and the butylene copolymer.

In one embodiment of the invention, neckable nonwoven web face 12 can be a multilayer material.For example, with one deck spunbonded webs at least with one deck meltblown web face, bonding carded wire side or other suitable material combine at least.Perhaps, neckable nonwoven web face 12 can also be a monolayer material.For example spunbonded webs, melt and spray wire side or bonding carded wire side.

The composite that neckable nonwoven web face 12 also is mixed and made into by two or more different mixed with fibers or fiber and particle.Fiber and/or particle added in the air-flow that transmits meltblown fibers can form such mixture, promptly produced the mixture that meltblown fibers and other material closely tangle before meltblown fibers is collected into receipts grain equipment, this has just formed meltblown fibers and the random adhesion wire side that scatters of other materials.The other materials that mixes with meltblown fibers such as wooden oar, artificial fibre and particle etc., hydrocolloid (aquogel) particle of particle as being commonly called high hygroscopic material.

The nonwoven web of fiber should be by bonding form can anti-contraction the adhesion net surface structure.The bonding technology that is fit to comprises chemical bonding, hot adhesion, for example puts calendering, water entanglement and knitting technology etc., also is not limited thereto certainly.

Fig. 3 is the enlarged perspective of the preferred embodiment of mechanically stable device 38.This mechanically stable device comprises two applicators in opposite directions.Applicator has three-dimensional surface and cooperatively interacts at least to a certain extent.Mechanically stable device 38 shown in Fig. 3 is made up of incremental stretching roller 34 and 36.When the incremental stretching roller when the direction of arrow is rotated, neckable nonwoven web face 12 passes by

incremental stretching roller

34 and 36 formed nips 32.Last incremental stretching roller 34 comprises many teeth 40 and corresponding grooves 41, and these teeth and groove extend around the whole circumference surface of roller 34.Following incremental stretching roller 36 also comprises many tooth 42 and corresponding recesses 43 that extend around the roller circumferential surface.Tooth 40 on the roller 34 is meshed with groove 43 on the roller 36 or cooperates, and the tooth 42 on the roller 36 is meshed with groove 41 on the roller 34 or cooperates.

Tooth 40 on the roller 34 and the tooth 42 on the roller 36 are separately along extending with the perpendicular direction of neckable nonwoven web face 12 first directions or along the direction that parallels with nonwoven web 12 widths.That is

tooth

40 and 42 with horizontal or direction that the CD direction parallels on extend.Incremental stretching

roller

34 and 36 directions that promptly are parallel to first direction along the direction vertical with shrinkage direction are opened up cumulatively and are shunk a wire side, shrink nonwoven web 12 stabilisations thereby make.Like this, pass incremental stretching

roller

34 and 36 shrinking nonwoven web, the tensile force of executing thereon discharges, the nonwoven web state that still remains retracted.By shrinking the nonwoven web stabilisation.Shrink the size after nonwoven web will keep it to shrink substantially, can not reply its previous size.

After contraction nonwoven web 12 passes

incremental stretching roller

34 and 36 experience stabilization processes, a large amount of stabilisation burrs 44 will appear in stable contraction nonwoven web 12.The whole width that stabilisation burr 44 runs through stable contraction nonwoven web 12 extends along the linear direction that is parallel to each other.Stabilisation burr 44 be shown as with CD to or the direction that laterally parallels on extend.As shown in Figure 3, every stabilisation burr all is that a end margin from stable contraction nonwoven web extends to other end edge.This is very important, because this makes fiber run through the whole width setting of wire side, thereby stablizes wire side.Do not extend if stabilisation burr 44 runs through whole neckable nonwoven web face 12, the collapsible wire side of part that does not then extrude burr will be replied its previous width.For example, interval relief pattern shown in Figure 8 stabilisation nonwoven web effectively.Nonwoven web between each burr partly can not get setting and replys its previous size.

Incremental stretching

roller

34 and 36 can comprise the tooth and the groove of any amount.So that make nonwoven web reach desirable degree of stability.In addition, tooth and groove can be non-linear, for example curve, sine, zigzag etc.The size of tooth and engagement and quantity also can depend on the circumstances on the incremental stretching roller 34 and 36.In addition, the distribution arrangement of tooth and groove also not necessarily along with the perpendicular direction of nonwoven web feeding direction.For example, tooth and groove can be along extending to angled direction with CD.But had better not be parallel to MD to or machine direction because the expansion of this class incremental stretching is the width of wire side, be that the purpose of shrinking with wire side is inconsistent.

Referring now to Fig. 1,, neckable nonwoven web face 12 passes after the mechanically stable device 38, is wound on the material receiving roller 50.After the neckable nonwoven web face is stabilized in its contraction state it is wound on the material receiving roller with contraction state, is convenient to next step use.In case the neckable nonwoven web face is by mechanically stable or after formalizing, it just is adapted at having processed on the high speed conventional diaper process equipment, does not need other special process equipment.In addition, also can use conventional knot to knit equipment knits neckable nonwoven web face 12 knots in box and deposits.

Stable contraction nonwoven web can extend along the direction that is parallel to shrinkage direction at an easy rate.Promptly stable contraction nonwoven web can be at an easy rate along horizontal expansion or elongation.Stable extensible necked nonwoven web can uphold 60% at least under the tension force effect, and can not take place of serious failure (length after promptly exhibition is opened be at least when not applying tension force under the relaxation state length 160%).Preferably, stable extensible necked nonwoven web under the tension force effect, can uphold at least 100% and do not take place of serious failure (length after promptly exhibition is opened be at least when not applying tension force under the relaxation state length 200%).Because being extending but not resilient, stable extensible necked nonwoven web, stable extensible necked nonwoven web after exhibition tension force discharges, can not recover 55% of its stretch amount.Can not recover 25% of stretch amount after preferably discharging exhibition tension force.

Under situation about imposing than low-tension, stable extensible necked nonwoven web preferably can uphold at least 60%, and preferred situation is to uphold 100% even more and do not take place of serious failure.Owing under than the low-tension effect, can produce at least 60%, preferred 100% even more stretch amount.This just makes stable extensible necked nonwoven web be particularly suitable for making disposable absorbent article.For example, similar articles for use such as diaper, incontinent brief, training pants, feminine hygiene clothing.Reason is that they can be used in the position that needs high ductibility on the articles for use and assist body fitting.

Stable extensible necked nonwoven web is under the tension force effects less than 300 grams, and preferred stretch amount is at least 60%, can reach 100% and do not take place of serious failure under the preferred situation.Tension force is just more preferred less than 200 grams, and tension force less than 100 grams just most preferably.

Owing to can be known by people with conventional drive unit and other conventional equipment that device shown in Figure 1 uses, for the purpose of clear, just in the schematic diagram of Fig. 1, do not drawn.

Except incremental stretching, also have additive method to be suitable for mechanically stabilized contraction nonwoven web.These methods comprise uses crimping roller and/or crease roller.The another kind of method that is fit to comprises making shrinks the nip that nonwoven web passes a pair of smooth surface roller formation.The roller engagement clamping force of setting this class stabilisation roller formation can make the contraction wire side reach desired stable degree.

Fig. 9 is the plane that another kind is suitable for stablizing the burr pattern of neckable nonwoven web face.This pattern comprises in a large number along running through the linear burr 210 of wire side 205 whole width with laterally parallel direction.This pattern also comprise many along with laterally extend through the linear burr 212 of the whole width of wire side 205 at an angle continuously at an angle and with burr 210.Wire side 205 also comprises the linear burr 214 of the whole width that runs through wire side 205 that a plurality of edges and horizontal angled and direction that also form an angle with

burr

210 and 212 are extended continuously.Angle between the

burr

212 and 214 can be arbitrarily and the angle of 210 of the two and burrs also can be any.

Figure 10 is the plane that another kind is suitable for stablizing the burr pattern of neckable nonwoven web face.This pattern comprise many whole wire side width that run through wire side 220 and with the burr 222 that laterally extends continuously at an angle.Wire side 220 also comprises many along with laterally angled and extend through the burr 224 of whole wire side 220 width continuously with the direction that burr 222 forms an

angle.Burr

222 and 224 is preferably orthogonal.But, also can adopt other angle between the

linear burr

222 and 224.

Send the nip that forms by a pair of dandy roll tube to and can extrude the burr pattern shown in Fig. 9 and Figure 10 by shrinking nonwoven web.Comprise some convex surfaces on each roller, be similar to tooth 40 and tooth 42 on

roller

34 and 36 respectively.Convex surfaces on each roller is complementary, can be engaged with each other and exert pressure to shrinking nonwoven web, makes it to produce the burr pattern shown in Fig. 9 and 10.The pressure that the embossing roller provides makes each bar fiber setting, thereby makes whole wire side be stabilized in its contraction state.

Another kind of scheme is, the dandy roll cartridge can also have the lines roller of certain pattern convex surfaces and the basal plane roller of a surface smoothing is formed by one.Convex surfaces on the lines roller leans against presses the contraction nonwoven web can generate the burr pattern shown in Fig. 9 and 10 on the basal plane roller.

Stable extensible necked nonwoven web can combine with elastic component in processing in the future.Form composite elastic material.Preferred situation is that extending shrink-down material stable when elastomeric material is in unstretched state combines with it.No matter elastic component is in extended state or unstretched state.Stable extensible necked nonwoven web and elastic component all can mutually combine with interruption or continuous mode along its part co-extensive surface.Stable extensible necked nonwoven web can launch the back from the roller such as material receiving roller 50 and combine with elastic component, also can directly combine with elastic component after having implemented mechanically stable.

Elastic component can be made by any suitable elastic materials.Usually, any highly elastic fiber shaping resin or the mixture that contains above-mentioned resin all can be used to make the nonwoven web of elastomer.Film shaped resin of any high elasticity or the mixture that contains above-mentioned resin all can be used to make high elasticity film of the present invention.For example, elastomeric material can be to be the elastic membrane that the block copolymer of A-B-A ' is made by general chemical formula, and wherein A and A ' are the thermoplastic polymer block ends, comprise the styrene part, for example poly-(vinyl-arene).Wherein B is the elastomeric polymer stage casing, for example conjugated diene or low olefin polymer.Other typical elastic films that can be used for making elastic film comprise polyurethane (second) ester elastomer material, for example B.F.Goodrich ﹠amp; The product of the ESTANE brand of Company company; Polyamide elastomeric material, for example product of the PEBAX of Rilsan company brand; Polyester elastomeric material, for example product of the Hytrel brand of E.I.DuPont DeNemours company.

Polyolefin can also mix with elastomeric polymer to improve the machinability of mixture.When polyolefin mixes with elastomeric polymer and during the appropriate combination of the pressure and temperature condition that is subjected to raising, polyolefin must be a kind of and elastomeric polymer squeezable polyolefin under admixture.In the mixing polyolefine material that is suitable for comprises that polyethylene, polypropylene and polybutene, ethylene copolymer, propylene copolymer and butylene copolymer are also included within.

Elastic component can also be a kind of pressure-sensitive elastic binder sheet material.For example, itself is clamminess elastomeric material, perhaps can mix tackifying resin and add above-mentioned push in the elastic composite to and form the elastic sheet material that can be used as pressure sensitive adhesives, such as elastic sheet material is bonding with the nonelastic wire side that shrinks of having stretched.Elastic sheet material can also be that multilayer material constitutes, and it can comprise two-layer or more independent adhesion wire side or film.In addition, elastic sheet material can also be a multilayer material, and wherein one or more layers is comprising elastomer or particle and non-elastic fiber or granuloplastic mixture.

Other elastic material that is suitable as elastic component comprises " active (live) " synthetic rubber or natural rubber, comprises the thermal contraction elastic membrane, the elasticity scrim of shaping, similar substances such as elastic foam glue.In specific preferred embodiment, elastic component comprises the elasticity scrim of Conwed Plastics company.

Relation between the size after the original size of neckable nonwoven web face 12 and its drawn or the contraction has just determined the approximate exhibition of composite elastic material to open the limit.Because the neckable nonwoven web face is to open up the size of opening and being returned to contraction on certain orientation, shrinkage direction can be that machine direction also can be laterally, composite elastic spare with the same direction of neckable nonwoven web face 12 on also can open up and open.

For example, referring to Fig. 4,5,6, suppose to wish that a kind of span of opening up of preparation reaches 150% composite elastic material, profile is as shown in Figure 4 but not necessarily identical with Fig. 4 again shrinkable material width X of ratio is 250cm, stretched after-contraction is width 100cm, and label is Y.Contraction nonwoven web as shown in Figure 4 is made into stable extensible necked nonwoven web behind mechanical stabilization.Then stable extensible necked nonwoven web and width are about 100cm and can open up at least to open for the elastic component of width 250cm and combine.Generate with Fig. 6 profile similarity but the not necessarily identical composite elastic material of ratio has width Y is 100cm, and it can open up at least and open to 250cm, promptly elongation be shrinkable material original width 150%.As seen, the elastic limit of elastic component only need be expected the same big the getting final product of elastic limit with the minimum of composite elastic material from example.

Referring now to Fig. 7,, this figure has schematically illustrated another technical process 100 of making the contraction nonwoven web that the present invention mentions.

When feed roller 103 rotated around the direction of arrow shown in the roller side, neckable nonwoven web face 102 launched from feed roller 103, and along direction shown in the wire side upper arrow, promptly machine direction or first direction are sent to.The neckable nonwoven web face 102 that launches from feed roller 103 is through two the incremental stretching rollers 105 and the 106 formed nips 104 of horizontal wire side intensifier 107.Wire side intensifier 107 adopts two applicators in opposite directions, and applicator has three-dimensional surface and cooperatively interacts at least to a certain extent.Laterally wire side intensifier 107 comprises incremental stretching roller 105 and 106.The detailed description of horizontal wire side intensifier that comprises two incremental stretching rollers is referring to Fig. 2.

Contractile nonwoven web 102 can be made by known nonwoven extrusion forming process.For example, melt-blown process or the spunbond technology known of people.Then, make contractile nonwoven web, needn't in advance it be left on the feed roller directly through overpressure zone 104.

The neckable nonwoven web face of sending from horizontal wire side intensifier 107 102 will pass by the nip 125 of folding formula roller 128 and 130 formed S forming roll devices 126.The nip 125 of S forming roll device 126 is passed in neckable nonwoven web face 102 anti-S type path shown in the direction of rotation arrow on the folded formula roller 128 and 130.After passing from S forming roll device 126, neckable nonwoven web face 102 passes pressure roll cartridge 140 formed pressure nips 145, and device 140 comprises two exert pressure roller 142 and 144.Because the peripheral velocity of S forming roll device 126 is controlled to be peripheral velocity less than pressure roll cartridge 140, and neckable nonwoven web face 102 is stretched between the pressure nip of S forming roll device 126 and pressure roll device 140.By adjusting two groups of differences between the roller arrangement speed, the neckable nonwoven web face is stretched, and shrinks desired size and keep the state of this after-contraction that stretched.After passing from pressure roll device 140, shrink nonwoven web 102 and pass mechanically stable device 152 formed nips, device 152 comprises incremental stretching roller 153 and 154.Because the roller peripheral velocity of pressure roll device 140 is controlled to be the roller peripheral velocity that is less than or equal to mechanically stable device 152, nonwoven web is kept it and is stretched and/or contraction state between pressure roll device 140 and mechanically stable device 152.After mechanically stable device 152, stable contraction nonwoven web 102 is wrapped on the material receiving roller 160.In addition, also can use conventional equipment that stable contraction nonwoven web 102 knots are woven in the rewinding box.

Conventional drive unit and other conventional equipments of can the device in Fig. 7 using are known by people, for the purpose of clear, not shown in the schematic diagram of Fig. 7.

Measuring method

Utilizing micro image analysis methods analyst nonwoven web is the surface-pathlength of decidable nonwoven web.

Cut and isolate the sample that is used to measure from nonwoven web.After being attached on the wire side, go out half inch long not distortion sample length, accurately cut then, and separate from wire side in direction " gauging calibration " perpendicular to " measurement limit ".

To measure then on the long edge that sample is fixed to microslide." measurement limit " outwards pulled out slide edge (approximately 1mm) a bit a little.Coat very thin one deck contact adhesive in edge, can make sample fixing better like this towards slide.For sample with dark wrinkle.Need launch sample (not applying too big power) lightly, so that sample is easier to the slide EDGE CONTACT and adheres to.The property distinguished at edge when so just having improved graphical analysis has avoided appearance to need the possibility of additional explanation analysis " wrinkle " marginal portion.

Employing has the suitable microscopic measuring method of enough high-quality and multiplication factor, gathers the image of each sample from slide " edge " with " measurement limit " view.Utilize following equipment to come image data: Keyence VH-6100 (20 times of eyeglasses) video-unit, with the video image printout of Sony Video printer Mavigraph device making.Carry out the image scanning of video printout with HP ScanJet IIP scanner.Use 1.45 editions softwares of NIH MAC Image on MacIntosh IICi computer, to carry out graphical analysis.

When using this equipment, at first to come the computer image analysis program is demarcated setting as uncalibrated image with grid with length 0.500 ", increment be labeled as 0.005 ".Want measured sample to carry out video imaging and video image printing to all then.Next step is suitable Mac image file format with all video printouts with 100dpi (256 grades of gray scales) image scanning.At last, use each image file of Mac Image1.45 computer program analysis (comprise and demarcate file).All samples will adopt selected free-hand line measurement instrument to measure.Measure at the edge, two sides of sample and with under the length records.Thin sample only need be measured an edge.Thick sample need be measured two-sided edge.Whole measuring length along the cutting sample is carried out linear measure longimetry.In some cases, whole cutting sample be covered and a plurality of (overlapping) image may be needed.In these cases, selecting the common feature of overlapped image and be used as " mark ", is to adjoin to read and non-overlapped reading when making reading images length.

With 5 independent 0.5 of every section wire side " length of metering sample averages and can obtain the last determined value of surface-pathlength.Each metering sample " surface-pathlength " is the mean value of two-sided edge surface path.

Although above-mentioned measuring method all is suitable for many wire sides of the present invention, may make amendment by needs for adapting to some wire sides.

Although specific embodiment of the present invention has been illustrated explanation and has described, those do not depart from multiple other variations of invention essence and scope and change should be conspicuous for the ordinary skill in the art.Therefore attempt variation in all these scope of the invention and change are covered in the appended claims.

Claims

1. method of making stable extending nonwoven web, described method is characterised in that the following step:

A) provide the neckable nonwoven web face, preferably by other hygroscopic material of fiber and one or more composite material mixed mutually;

B) the neckable nonwoven web face is sent to along first direction;

C) make the neckable nonwoven web face along bearing incremental stretching with the perpendicular direction of described first direction, preferably nonwoven web is sent into the nip that is made of a pair of incremental stretching roller, described roller preferably has a plurality of teeth and a plurality of groove;

D) the neckable nonwoven web face being applied tensile force shrinks nonwoven web;

E) make the contraction nonwoven web bear mechanical stabilization, make stable extensible necked nonwoven web, preferably will shrink nonwoven web and send into the nip that is made of a pair of embossing roller, wherein said embossing roller preferably provides the continuous pressurization stabilisation burr that runs through whole nonwoven web width.

2. the method for claim 1 is characterized in that, makes the contraction nonwoven web bear incremental stretching along the direction parallel with described first direction in step e).

3. the method for claim 1, it is characterized in that, described neckable nonwoven web face is a kind of wire side of selecting from following material group: bonding carded fibers wire side, spun-bonded fibre wire side, meltblown fibers wire side, and the multilayer material that comprises at least a described wire side.

4. method as claimed in claim 3 is characterized in that, described fiber comprises a kind of polymer of selecting by in the following material group: TPO, polyesters and polyamide-based.

5. as method as described in the claim 4, it is characterized in that described polyolefin is selected: one or more in polyethylene, polypropylene, polybutene, ethylene copolymer, propylene copolymer and the butylene copolymer from following material group.

6. method according to claim 1, it is characterized in that, described neckable nonwoven web face is the composite that has comprised fiber and one or more other materials mixtures, and these one or more other materials are chosen from following material group: wooden oar, artificial fibre, particle and superabsorbent material.

7. method according to claim 1 is characterized in that, comprises following additional step:

F) stable extensible necked nonwoven web is combined with elastic component, preferably a kind of elastomeric polymer of from following material group, selecting of described elastic component, elastic polyolefin class, elastic polyurethane ethyl ester class, elasticity is polyamide-based and elasticity A-B-A ' block copolymer class, wherein A is identical or different thermoplastic polymer with A ', and B is the elastomeric polymer section.

8. method as claimed in claim 7 is characterized in that described elastic component comprises elastic membrane.

9. method as claimed in claim 7 is characterized in that described elastic component comprises the elasticity scrim.

10. method of making stable extending nonwoven web, described method is characterised in that the following step:

A) provide the neckable nonwoven web face, preferably other hygroscopic material of fiber and one or more mixes the composite of formation mutually;

B) the neckable nonwoven web face is sent to along first direction;

C) make the neckable nonwoven web face bear incremental stretching with the perpendicular direction of described first direction, preferably nonwoven web is sent into the nip that is made of a pair of incremental stretching roller, described roller preferably has a plurality of teeth and a plurality of groove;

D) along the direction parallel the neckable nonwoven web face is applied tensile force, make nonwoven web along shrinking with the perpendicular direction of described first direction with described first direction;

E) make the contraction nonwoven web bear the incremental stretching effect that parallels direction with described first direction.